Ulmer draws on the rich Hispanic culture of northern New Mexico for her first novel, launching a series that will follow the church calendar through its yearly cycle. What the book lacks in mysticism and epic plot, it makes up for with a natural prose style and vivid descriptions of the striking desert landscape. A widow and, like Ulmer, an ex-lawyer, Christina ""Christy"" Garcia y Grant owns La Casa Vieja Bed and Breakfast in Taos, N.Mex., a sleepy town whose biggest excitement is the Holy Week leading up to Easter. The Brotherhood of Our Lord Jesus is the focal point of this annual ceremony, with the penitentes (members of the brotherhood) performing a chanting pilgrimage toward the morada (prayer hall). When brother Eusebio Salazaar is found stabbed to death on Good Friday, suspicion falls on his cousin Patricio. Drawn to the case, Christy assembles a team of diverse characters to find the truth: Mac McCloud, a vacationing doctor who seems more interested in courting Christy than in helping the accused; Ignacio ""Iggy"" Baca, the pudgy, opera-loving public defender; and aging yet stalwart ""la Do a"" Doris Jordan, a senior advocate. As the four identify numerous shady suspects, from modern-day witches to top-secret Los Alamos nuclear research facility employees, it becomes clear that Eusebio's death was more than a random act of violence. Ulmer offers a notable literary mystery that will intrigue and amuse in equal measure. (Apr.)